1. Field of the Invention
The present invention relates to a mounting device for mounting a lens barrel of a camera on a support structure, such as a tripod or a monopod. More particularly, the present invention relates to a mounting device having a rotatable ring unit and a mounting seat integrally formed as a single unit, wherein the mounting device allows the support structure to be attached to either the ring unit or the mounting seat.
2. Description of the Related Art
In a camera having a relatively large lens barrel, a photographer typically mounts the lens barrel on a support structure to provide support for the lens barrel. The support structure can be, for example, a tripod or a monopod. The support structure provides stability to the camera and reduces the effect of vibrations on the camera. Thus, a support structure reduces the effect of image blur on a photograph resulting from, for example, hand tremor of the photographer.
A support structure is particularly effective in reducing image blur during photography with a heavy camera. For example, a telephoto lens is relatively heavy. Therefore, a telephoto lens is often equipped with a mounting device for mounting the telephoto lens on a support structure.
A conventional mounting device often includes a ring unit which supports the body of the lens barrel. The inner surface of the ring unit is arranged around the outside surface of the body of the lens barrel. A lens compartment holds a lens and is contained inside the body of the lens barrel. A mounting seat is connected to the ring unit via an arm. The mounting seat extends in the optical axis direction of the lens barrel. The arm causes a fixed space to exist between the mounting seat and the ring unit. A threaded hole is arranged in the mounting seat. When a photographer desires to use a support structure to take a photograph, a male thread (such as a screw) on the support structure is fit into the threaded hole of the mounting seat, to thereby mount the lens barrel on the support structure via the mounting seat. To transport the lens barrel. The photographer inserts his hand into the space between the mounting seat and the ring unit. In this type of mounting device, the mounting seat is connected directly to the support structure. The support structure cannot be connected directly to the ring unit. In addition, the lens barrel usually has a focusing ring which is rotated to focus the camera, and the mounting seat can become an obstruction when the photographer uses the focusing ring to focus the lens barrel.
A different type of mounting device has a ring unit, but does not include a mounting seat. Female threading is arranged directly in the ring unit. The ring unit can then be directly connected to the support structure, to mount the lens barrel on the support structure. This type of mounting device has an advantage in that it does not require a mounting seat. As previously mentioned, a mounting seat can become an obstruction when focusing the lens barrel via a focusing ring.
An additional type of mounting device has a ring unit and a mounting seat which is detachable from the ring unit. Female threading is arranged directly on the ring unit to connect the ring unit to the support structure. The mounting seat is attachable and detachable to the ring unit via screws on the mounting seat which fit into the female threading of the ring unit. The mounting seat can be attached to different positions on the ring unit. To perform photography, the photographer can detach the mounting seat from the ring unit, or attach the mounting seat to an appropriate position on the ring unit in accordance with the type of support structure being used. The mounting seat can then be attached to a support structure to mount the lens barrel on the support structure and provide support for the camera.
However, attachment and detachment of the mounting seat to and from the ring unit can be cumbersome and difficult to perform. Moreover, "play" can arise when the male screw of the mounting seat and the female threading of the ring unit are not accurately tightened together. This "play" is undesirable and can cause movement of the camera. Further, this "play" can cause contacting parts between the mounting seat and the ring unit to wear or break.
Further, the ring unit and the detachable mounting seat are two separate components. A number of required screws (for attaching the mounting seat to the ring unit) represent additional, separate components which increase the total number of separate components of the mounting device. Thus, a mounting device having a detachable mounting seat requires a relatively large number of separate components, thereby undesireably increasing the manufacturing costs and the number of steps in the manufacturing process.